The present invention relates to a brake disc comprising a support jaw integrally provided to project radially outwardly from one end of a cylindrical portion of the disc, and a pair of annular, ring-like slide plates secured on opposite sides of the support jaw by a plurality of radially extending ribs interposed therebetween.
A conventional brake disc having similar components is known, for example, from Japanese Patent Application Laid-open No. 80535/84.
However, in the conventional brake disc, the annular slide plates disposed respectively on the opposite sides of the support jaw have the same wall thickness as the support jaw. This increases the distance between the outer surfaces of the slide plates and may require an increase in the distance between two arms of a brake caliper which straddles the brake disc, thereby reducing the rigidity of the caliper.
The present invention has been accomplished with such circumstances in view, and it is an object of the present invention to provide a brake disc wherein the distance between the outer surfaces of the annular slide plates can be reduced.